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South Feather Water and Power Agency water division manager Matt Colwell, right, points out the balance in managing water levels Wednesday as a panel of experts speaks about their experiences with water and dams as they review what could have gone wrong and look ahead to future construction on the Oroville Dam spillway, in the Bell Memorial Union at Chico State University. Colwell expanded on points made earlier by Glen Pearson, left. (Dan Reidel — Enterprise-Record)

Chico – With experience in geology, water management and negotiating hydropower licensing, four men brought their expertise to a panel discussion on the Oroville Dam spillway Wednesday at Chico State University.

The panel talked about issues with controlling the water and managing dams, in a program presented by Chico State’s Center for Water and the Environment and the school’s Department of Civil Engineering.

Every seat in the room of the second floor of the Bell Memorial Union was filled and, after a presentation from each panel member, questions from the audience had to be cut off because of time.

ASBESTOS IN THE ROCK

It’s not serpentine that caused the Butte County Air Quality Management District to increase monitoring and recommend extra measures to contain asbestos, but a rock called actinolite.

Russell Shapiro, chair of the Geological and Environmental Sciences Department and one of the panel members, got a good look at the rock and was able to take some samples on a tour of the site earlier this month.

The geology professor said there is a complex mix of sedimentary and volcanic rock.

“It’s good rock to build a dam on,” Shapiro said.

There are also “belts of fibrous minerals” and those minerals “got us interested,” he said.

Using a scanning electron microscope and x-ray spectroscopy, Chico State geologists found several minerals but actinolite was prevalent.

“The reason this is an issue is actinolite is one of the known carcinogenic-asbestos minerals,” Shapiro said.

The professor said all the research is still in the early stages and both the air quality district and the Department of Water Resources are studying their own samples.

CONTROLLING THE FLOOD POOL

There’s a method and timing that DWR has to follow to properly manage the water in any reservoir, and one of the great challenges is balancing the inflow to the outflow, said Glen Pearson, a retired DWR engineering geologist who now teaches at the university.

Having a broken spillway increases that challenge.

The Army Corps of Engineers requires reservoirs be kept at a certain level, called the “flood pool” which varies depending on whether it is a wet or dry year. Pearson said the corps directs the DWR to keep the lake at that level so that when heavy rain and snow do come, the flood pool fills and water can be released gradually to prevent flooding.

“We’ve got to get the water out of there because we have all this snow and we don’t know what’s going to happen,” he said.

South Feather Water and Power water district manager Matt Colwell also talked about balancing the water level and said predicting how much water would come into the reservoir is a stochastic process, which means random variables can affect the reliability of the prediction.

SPILLWAY FAILURES

The fourth panelist, Dave Steindorf, talked about how infrastructure needs improvement and pointed to the emergency spillway as an example.

“My colleague from DWR said, ‘We aren’t going to use it,’” he said, echoing what the water agency said of the emergency spillway in an early February press conference which Steindorf attended. “Obviously that situation got away from them.”

The special projects director for the nonprofit American Whitewater has been a part of the negotiations on the relicensing of the Orovile Dam between the Federal Energy Regulatory Commission and the Department of Water Resources. American Whitewater is responsible for monthly high water releases in the Feather River Canyon for whitewater kayaking and rafting.

Steindorf said DWR had been warned that issues related to using the emergency spillway, but did not address them.

“We were told during relicensing (the emergency spillway) could handle 350,000 cfs,” he said. “It nearly failed at 3 percent of the rated flow.